Seal for glass oven door



April 5, 1966 L. v. BUCK SEAL FOR GLASS OVEN DOOR Filed Aug. 31. 1964 United States Patent 3,244,165 SEAL FQR GLASS (OVEN DOGR Leo V. Buck, Effingham, 11]., assignor to Borg-Warner Corporation, Chicago, H1, a corporation ct Illinois Filed Aug. 31, 1964, Ser. No. 393,306 Claims. (Cl. 126-200) The present invention relates to oven doors having windows permitting viewing of an oven interior and more particularly to the mounting of the window in the oven door.

It is helpful to a housewife using an oven to have a door which permits viewing the food as it is baked, roasted, or broiled. However, in providing such windows for oven doors several problems are encountered. It is necessary that the window not permit the escape of heat to any substantial degree from inside the oven into the environment surrounding the oven, ordinarily the kitchen. The practice has been to provide a pair of glass panels spaced apart to form an air space that serves as an insulator. In mounting the window panels in a door, a seal must be provided to prevent the deposition of discoloring product on the inside surface of the glass panels, i.e., on the side of the glass panels facing the air space. The discoloring product is carried by vapors created in the oven. The seal, however, must not require a precise thickness of glass because in practice, glass plate thickness is not maintained to precise tolerances. Furthermore, the external or exposed side of the seal must permit air flow into and out of the insulating air space. This is because as the temperature of the air space changes the pressure changes, i.e. a rise in temperature increases the pressure while a drop in temperature creates a vacuum. The air must move into and out of the space to substantially equalize the pressure therein with the atmospheric pressure outside.

Accordingly, it is an object of the present invention to provide an improved mounting for window panels used in oven doors and the like, which mounting prevents entry of greasy vapors and the like into the air space between the pair of spaced apart glass panels While permitting movement of relatively clean air into and out of the air space to equalize pressures therein with those of the outside environment.

It is the overall object of the present invention to provide .an economically manufacturable and easily installed window mounting for an oven door and the like adaptable for use in standard units.

Other objects and advantages of the invention will become apparent upon reading the following detailed description and upon reference to the drawings in which:

FIGURE 1 is a portion of an oven door in elevation embodying the present invention;

FIGURE 2 is a section taken along 22 in FIG- URE 1;

FIGURE 3 is a section taken along 33 in FIG- URE 1.

While the invention will be described in connection with the preferred embodiment, it will be understood that I do not intend to limit the invention to that embodiment. On the contrary, I intend to cover all alternatives, modifications, and equivalents as may be included within the spirit and scope of the invention and defined by the appended claims.

Referring more particularly to the drawings, FIGURE 1 is an elevational view of a portion of an oven door which ordinarily would be hingedly mounted at the front end of an oven enclosure. The door, when closed, separates the heated oven interior from the relatively cool room in which the oven is located. In ordinary use, the oven would be heated to a high temperature, for example Patented Apr. 5, 1966 "ice 300 to 500 for baking, roasting, or broiling food placed therein. The window 11 permits viewing while cooking is progressing. The door 10 is comprised of an internal panel 12, forming an inside wall 12a, and external panel 14, forming an outside wall 14a. The panels are constructed so that they can be assembled, and they are held together by suitable fastening means, for example a screw and anchor assembly 15. Though a single assembly 15 is shown, there would be a plurality spaced about the window 11. The respective panels 12, 14, have interfitting peripheral portions, and the respective internal and external walls 12a, 14a, are selectively drawn towards each other by tightening a series of screws 16, which thread in respective anchors 18, comprising the assembly 15.

Turning to Window 11, it is formed by providing a pair of aligned openings 19, 20, respectively in the panels 12, 14. In the present instance, a pair of flanges 21, 22, respectively, formed as an integral part of the panels 12, 14, extend about the perimeter of each of the respec tive openings 19, 20. Iositioned in juxtaposed relationship to the respective panels 12, 14, are a pair of glass panes or panels 24, 25, forming an insulating air space 23. The panels are maintained in spaced apart relationship, in the present instance, by a generally U-shaped spacer 26. To provide a bias on the respective window panels 24, 25, pushing them toward respective flange edges 21a, 22a, the spacer 26 is provided with a pair of legs 28, 29, extending from a body portion 31 The legs react to an inward bending force and cooperate with the screw and anchor assemblies 15, to draw the panels 12, 14, together, i.e., clamping the glass panels in position. Longitudinal or vertical support for the glass panels is provided by a support bracket 31, extending about the periphery of the glass panels and suitably fastened to one of the door panels, in the present instance spot welded to internal door panel 12. As is clear from FIGURE 2, the edges 32, 34 of the glass panels 24, 25, rest on cushioning means, constructed for example of asbestos inserts 35, which along the bottom carry the weight of the glass. The inserts 35, can either be a single piece extending all the way around the glass or include a series of individual portions interposed in spaced apart relation between the junction of the glass edges, and support bracket 31. The purpose of the inserts is to absorb shocks resulting from rough handling of the door 10, and thereby prevent chipping or breaking of the glass. As is emphasized subsequently, the inserts do not form an air-tight seal.

In accordance with the present invention an improved glass panel mounting assembly 36 is provided for effecting an air-tight seal between the internal door panel 12 and the internal window panel 24 and an air-flow fit between the external door panel 14 and the external window panel 25. As herein illustrated, an alir-tight seal is effected by pressing a peripheral portion 39 of the internal glass panel 24 against a flexible sealing means 40. In the preferred embodiment, the sealing means 40 takes the form of a small diameter hose extending about the perimeter of the opening 19 and is constructed of suitable heatresistant, flexible material, for example silicone rubber. A channel 41, is provided to hold the sealing means 40, in position and also form walls against which the sealing means can be pressed, and distorted. The channel 41, extends about the perimeter of the opening 19, and, in the present instance, is formed by the support bracket 31, a peripheral portion 42, of internal door panel 12, and flange 21. As is clear from FIGURE 2, the support bracket 31, is positioned outboard of the flange 21. It is, of course, possible to use a bonding agent to attach the sealing means 40, to the peripheral portion 42, thus, not

J) requiring the flange 21, which supports the sealing means and prevents its sliding toward the opening 19, and out-ofposition. Furthermore, the sealing means can take other cross section forms such as rectangular, and also it can be solid instead of having an opening extending therethrough. It must be constructed of material which can flex and thereby intimately contact the glass panel 24. Accordingly, grease vapors formed during cooking of food in the oven are prevented from entering the air space. There is no opportunity for discoloring materials to deposit on the inside surface, the side facing the air space, to impede viewing and give an unpresentable appearance to the oven window 11.

To permit communication between the air space 23, and the outside environment, the fit between the external dooor panel 14, and external glass panel 25, is not air tight. This permits equalization of the pressures in the air space 23, with those outside of the oven, as during ordinary use, the temperatures in the oven, and therefore of the air space rise and fall. In the illustrative embodiment, the edge 22a of the flange 22, engages a peripheral portion 44 of external glass panel 25. Accordingly, when the door is assembled and the plurality of screw and anchor assemblies are tightened, the outside panel 14, is drawn toward the inside panel 12. As a result a clamping action is applied to the respective window panels 24, 25. The spacer 26 takes up any variations in glass thickness and transmits force to the inside glass panel 24, which acts on the sealing means 40. As a result of the applied pressure the sealing means 49 is distorted and intimately contacts both the glass panel and door panel.

As shown in FIGURE 3, the sealing means 40 extends about the respective corners. The legs 2%, 29' of the support brackets 31 are cut-away to permit bending of the bracket. In the illustrative improved window mounting structure the bracket and peripheral portion 39 of the internal door panel surrounding the opening 19, cooperates to support the sealing means.

What is claimed is:

'1. In an oven door the combination comprising a pair of panels assembled to form respective internal and external door walls, said walls supported in spaced apart relationship and having therein aligned openings; an inwardly projecting flange carried by said internal panel; a support bracket carried by one of said panels and extending across the space between said panels, said bracket spaced outboard of the perimeter of said internal door panel opening to form a channel with said flange; a flexible heat resistant sealing member positioned in said channel; an internal glass panel positioned in juxtaposed relationship with respect to said internal door panel and having a peripheral portion in pressing engagement with said sealing member; an external glass panel positioned substantially parallel and in spaced relationship with respect to said internal glass panel; a spacer positioned between said glass panels and exerting an outward spring force thereon to maintain said panels in spaced apart relationship; means carried by said external door panel engaging said external glass panel; and means for holding said internal and external door panels together whereby pressure is applied by said internal glass panel periphery to said sealing member, distorting the latter and eifectuating an air-tight seal between said internal glass panel and said internal door panel.

2. In an oven door the combination comprising a pair of panels assembled to form respective internal and external door walls, said walls supported in spaced apart relationship and having aligned openings therein, an ind Wardly projecting flange carried by said internal panel and extending about the perimeter of said internal panel opening; a support bracket carried by one of said door panels, said bracket spaced outboard of said flange and forming therewith a channel; a flexible heat resistant sealing member positioned in said channel; an internal glass panel positioned in juxtaposed relationship with respect to said internal door panel and having a peripheral portion in pressing engagement with said sealing member; an external glass panel positioned substantially parallel and in spaced relationship with respect to said internal glass panel; a spacer positoned between said glass panels and exerting an outward spring force thereon to maintain said panels in spaced apart relationship; means carried by said external door panel engaging said external glass panel; and means for holding said internal and external door panels together whereby pressure is applied by said internal glass panel to said sealing member, distorting the latter and efliectuating an air-tight seal between said internal said support bracket, said means permitting flow of air between said external door panel and external window panel to substantially equalize pressure in the air space between said internal and external window panels and pressure outside of the oven.

5. In an oven door the combination comprising a pair of panels assembled to form respective internal and external door walls, said walls supported in spaced apart relationship and having therein aligned openings; a support bracket carried by one of said panels and extending across the space between said panels, a flexible heat resistant sealing means; support means for mounting said sealing means on a peripheral portion of said internal panel wall surrounding said panel opening; an internal glass panel positioned in juxtaposed relationship with respect to said internal door panel and having a peripheral portion in pressing engagement with said sealing means; an external glass panel positioned substantially parallel and in spaced relationship with respect to said internal glass panel; a spacer positioned between said glass panels to maintain said panels in spaced apart relationship; means carried by said external door panel engaging said external glass panel; and means for holding said internal and external door panels together whereby pressure is applied by said internal glass panel peripheral portion and to said sealing means, distorting the latter and efiectuating an air-tight seal between said internal glass panel and said internal door panel.

References Cited by the Examiner UNITED STATES PATENTS 2,377,684- 6/1945 Firner 2056.5 2,535,589 12/1950 Mills l26200 2,582,458 1/1952 Rose 126200 3,021,832 2/1962 Mills 126200 3,127,890 4/1964- Mills 126-200 3,151,612 19/1964 Keeling et al. 12620O KENNETH W. SPRAGUE, Primary Examiner. 

1. IN AN OVEN DOOR THE COMBINATION COMPRISING A PAIR OF PANELS ASSEMBLED TO FORM RESPECTIVE INTERNAL AND EXTERNAL DOOR WALLS, SAID WALLS SUPPORTED IN SPACED APART RELATIONSHIP AND HAVING THEREIN ALIGNED OPENINGS; AN INWARDLY PROJECTING FLANGE CARRIED BY ONE OF SAID INTERNAL PANEL; A SUPPORT BRACKET CARRIED BY ONE OF SAID PANELS AND EXTENDING ACROSS THE SPACE BETWEEN SAID PANELS, SAID BRACKET SPACED OUTBOARD OF THE PERIMETER OF SAID INTERNAL DOOR PANEL OPENING TO FORM A CHANNEL WITH SAID FLANGE; A FLEXIBLE HEAT RESISTANT SEALING MEMBER POSITIONED IN SAID CHANNEL; AN INTERNAL GLASS PANEL POSITIONED IN JUXTAPOSED RELATIONSHIP WITH RESPECT TO SAID INTERNAL DOOR PANEL AND HAVING A PERIPHERAL PORTION IN PRESSING ENGAGEMENT WITH SAID SEALING MEMBER; AN EXTERNAL GLASS PANEL POSITIONED SUBSTANTIALLY PARALLEL AND IN SPACED RELATIONSHIP WITH RESPECT TO SAID INTERNAL GLASS PANEL; A SPACER POSITIONED BETWEEN SAID GLASS PANELS AND EXERTING AN OUTWARD SPRING FORCE THEREON TO MAINTAIN SAID PANELS IN SPACED APART RELATIONSHIP; MEANS CARRIED BY SAID EXTERNAL DOOR PANEL ENGAGING SAID EXTERNAL GLASS PANEL; AND MEAND FOR HOLDING SAID INTERNAL AND EXTERNAL DOOR PANELS TOGETHER WHEREBY PRESSURE IS APPLIED BY SAID INTERNAL GLASS PANEL PERIPHERY TO SAID SEALING MEMBER, DISTORTING THE LATTER AND EFFECTUATING AN AIR-TIGHT SEAL BETWEEN SAID INTERNAL GLASS PANEL AND SAID INTERNAL DOOR PANEL. 